The XE variant is recombinant, meaning that it consists of genetic material from two other strains, which in this case are BA.1, the original omicron strain, and BA.2, known as the “stealth omicron”. According to an epidemiological report released March 29 by the World Health Organization, estimates show that XE is 10% more contagious than BA.2, but the findings need further confirmation. The variant was first identified in the United Kingdom in mid-January and since then 600 cases have been reported in the country. The UK Health and Safety Administration said it was monitoring XE along with two other recombinants, XD and XF, which consist of Delta and BA executives. The UK health authorities explained in late March that there was insufficient evidence to draw conclusions about the growth advantage or other properties of this variant, but examined initial reports of its infectivity. “This particular recombination, XE, has shown a variable growth rate and we can not yet confirm whether it has a real growth advantage,” said Susan Hopkins, UKHSA Chief Medical Advisor. The recombinant variants themselves, however, are not uncommon, according to health officials. “Recombinant variants are not uncommon, especially when many variants are circulating and several have been identified during the pandemic to date,” Hopkins said. “As with other variants, most will die relatively quickly.” The WHO said it would “continue to monitor and closely assess the public health risk associated with the recombinant variants” and would “provide updates as further evidence is available”.
